This retrospective study sought to compare a new implant (Astra Tech OsseoSpeed
EV) with its predecessor (Astra Tech OsseoSpeed TX) by scanning electron
microscopy and interferometry. Radiographic data from 19 patients who underwent
implant restoration with EV (n = 49) with a median follow-up of 16 months were
evaluated for mean bone level (MBL) changes from delivery of the definitive
prosthesis. EV and TX did not differ in surface roughness, and both systems had
a tight seal at the implant-abutment interface. The median MBL change of the EV
was −0.02 mm mesiodistally after a median follow-up period of 16 months. Greater
maintenance of MBL was found in the screw-retained restorations (n = 17) compared
to cemented (0.35 ± 0.33 mm and −0.38 ± 0.76 mm, respectively; P = .03). The
data suggest that EV shows minimal levels of bone loss and high implant survival.

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